This invention relates to electrical testing equipment and more particularly, to an improved housing for a voltage tester or voltmeter.
One of the components in a voltage tester is a pair of insulated electrical leads fitted with prod handles having contacts at the ends for connection to the points where the voltage is to be measured. The presence of these leads creates a problem of what to do with them when the tester is not in use. Also, in hand held units, the user has to manipulate the two prod handles in addition to the tester itself. Thus, the user has three items to hold in two hands. These problems were addressed in Mitchell, U.S. Pat. No. 2,791,748. Mitchell teaches the use of fully enclosed tubular passages integrally formed in the housing of the tester. The passages house the prod handles when they are not in use. The tips of the handles are wedged in the bottom of the passage to hold them in. Mitchell also uses a socketing means in the housing for mounting the base end of a prod handle so the tester housing and mounted prod can be manipulated as a unit.
The disadvantages of the tubular passages in Mitchell are that they are difficult to manufacture and they do not securely hold the prod handles. The metallic prod is easily dislodged from its wedging abutment so the handles become free to fall out of the passages if the unit is not held upright.
Another difficulty attendant with the voltage tester leads is they are prone to failure. The leads are typically subjected to rough handling such as yanking them out of test locations and picking the tester up by the leads. Locations particularly vulnerable to electrical failure are the junction between the contact pin in the prod handle and the lead wire, and the point where the lead wire enters the tester housing. In the past, there has been no way to make sure the leads have not been damaged. This becomes particularly critical in the field where the tester is used to detect the presence of a voltage before an electrician starts working on a system.